<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>首页</title>
</head>
<body>
<h1>欢迎</h1>
<form action="login.jsp?key=logout" method="post">
    退出登录：<input type="submit" name="sb">
</form>
</body>
</html>
